.rollBox{
    //background:white;
    position:relative;
    background-color: #f5f5f5
}
.rbg{
    position: absolute;
    height: 100%;
    width: 100%;
    z-index: 1;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    align-items: center;
}
.content{
    height: 100%;
    width: 100%;
    z-index: 100;
}